A solenoid is a common electrical device used to convert electrical energy into mechanical energy. Solenoids are well known in the art and are often utilized as a means of moving a component a predetermined distance at a predetermined time. In its most basic form, a solenoid is an electro-mechanical device that converts electrical energy into linear or rotary motion. Electrical current passes through a coil of insulated copper wire producing a magnetic field, which moves a ferro-magnetic plunger located within the core of the coil. Steel parts surround the coil to contain the flux path for maximum pull, push or rotational force. A solenoid can be used to open a valve, activate a switch, apply a brake or a number of other activities where mechanical movement is required and only an electrical energy source is available or practical.
A typical solenoid comprises a steel frame or shell that surrounds the coil of wire and directs the flux path. The coil assembly, when energized with an electrical voltage, creates the magnetic lines of force. A plunger, located within the coil assembly, reacts to the magnetic pull and moves to center itself within or along the coil toward and against a stop or pole piece. The pole piece provides a stop for plunger movement.
A solenoid system requires, at a minimum a solenoid and an electric control. In many applications, the electric control comprises an electronic control module. Most prior art solenoid systems require each individual solenoid and individual control module be connected to one another with a predetermined length of electrically conductive wire. While these prior art systems continue to be viable for many applications, the present invention advances the art by consolidating the multiple components into a single housing or enclosure.
While a controller located within a solenoid housing has been utilized in the past to control the movement of a solenoid, an integrated solenoid system having the structure and benefits, as set forth below, is believed to be novel. The inventor is aware of a product manufactured by the assignee of the present invention for Leslie Controls, Inc. of Tampa, Fla. known as a “Solicon” that incorporates a controller within the solenoid housing. However, the controller for the Solicon device is relatively complex, costly and requires considerable space. The inventor is also aware of a solenoid built by an unknown company in Poland that also places the controller within the housing. Again, temperature compensation is not provided in the control circuit and voltage compensation occurs only in a low power or “hold” mode of operation. Another major drawback of these designs resides in their overly large size and expensive circuitry. The inventor is not aware of any other prior art that teaches the unique combination of components and resulting benefits disclosed herein.